As is well known in the art, DIP devices consisting of a body portion, and attached and depending leads connected thereto for assembly onto a PCB or the like, are manufactured with the leads disposed in a particular arrangement adapted for insertion in the predetermined array or pattern of holes or sockets in a PCB. The material of the leads and their connection to, and disposition on, the DIP bodies frequently results in a bending or distortion of the leads due to handling during manufacturing operations. By placing DIP devices in plastic delivery tubes some protection is provided. However, such protection is limited.
As a result of the continued bending and distortion, a series of apparatus and methods have been developed to straighten or reorient DIP devices or to determine DIP leads integrity in order to evaluate whether a straightening operation is required. Examples of such DIP lead straightening apparatus and methods are disclosed in U.S. Pat. No. 3,880,205 for ELECTRONIC COMPONENT LEAD STRAIGHTENING DEVICE AND METHOD, and U.S. Pat. No. 4,481,984 for ELECTRONIC COMPONENT LEAD STRAIGHTENING DEVICE AND METHOD both owned by the Assignee of the instant application. Examples of such integrity determination apparatus and methods are disclosed in U.S. patent application Ser. No. 648,872, Pat. No. 4,686,637, for APPARATUS AND METHOD FOR LEAD INTEGRITY DETERMINATION FOR DIP DEVICES, filed Sept. 10, 1984, and U.S. patent application Ser. No. 735,857, now Pat. No. 4,704,700, for IMPROVED APPARATUS AND METHOD FOR LEAD INTEGRITY DETERMINATION FOR DIP DEVICES, filed May 20, 1984, both of which are ownedy by the Assignee of the instant invention.
In the past the delivery tubes were presented to such and similar apparatus by manually removing a pin or a plug from the end of each tube and thereafter manually inserting each tube in a receptacle attached to the apparatus. A typical DIP straightening apparatus included a turret arrangement of the type disclosed in the U.S. Pat. No. 4,481,984. Additionally, it was known to manually pre-orient DIP tubes by inserting a number of tubes into a magazine rack-type device. Such magazine rack-type devices typically only held 6 to 60 tubes at a time. Such manual operation was not only time consuming but also increased the possibility of further damage to the DIP devices.
Automatic handling of DIP tubes is illustrated in a pending application Ser. No. 807,531 for A METHOD AND APPARATUS FOR LOADING/UNLOADING DIP DEVICES, filed Dec. 11, 1985 and assigned to the common Assignee of the present application. This pending application is incorporated herein by reference in its entirety. In accordance with the method and apparatus disclosed therein, a plurality of DIP tubes can be placed into a hopper at random orientation. Orienting components, provided in the present invention, remove individual tubes from the hopper and orient the tubes to a predetermined radial orientation. In response to a control signal, the oriented delivery tube is moved axially in a direction for insertion into a head assembly. The head assembly receives the delivery tube from the orienting components and guides the tube to a predetermined axial orientation. After the transfer of DIP devices, the tube is ejected from the head assembly. A control member is also provided in the present invention to coordinate the movement of the orienting components and the head assembly. Such coordination is achieved through the generation of control signals, which signals cause the orienting components and head assembly to operate in predetermined controlled sequences.
The present invention is directed to novel improvements in the head assembly providing a number of functional advantages. For example, the particular configuration and arrangement of the head assembly facilitates easy and quick interchangeability of parts of the mechanism to remove plugs and pins from the tubes and reassembly thereof during loading and unloading operations.
Still another feature of the head assembly of the present invention is the dual drive system for actuating tubes during the loading and unloading cycle which provides a more positive controlled driving action and minimizes slippage.
Still another feature of the head assembly of the present invention is the provision of means for pulsing or agitating the tubes during the unloading or loading cycle to ensure complete emptying or filling thereof.
In accordance with another feature of the present invention, the head assembly includes a novel duck-bill linkage arrangement for centering the tubes relative to the discharge trackway thereof and a singulating wheel for unloading the DIP devices which minimize hang-up and ensures proper spacing during movement thereof to the next station in the system.
In accordance with another feature of the present invention, a rake assembly is provided which in tandem systems of the type illustrated in FIG. 1 provides a means for correcting DIP jamming adjacent the lower unit.